What is the greatest common factor of $4$ and $2$ ? Another way to say this is: $\operatorname{gcf}(4, 2) = {?}$
The greatest common factor is the largest number that is a factor of both $4$ and $2$ The factors of $4$ are $1$ $2$ , and $4$ The factors of $2$ are $1$ and $2$ Thus, the greatest common factor of $4$ and $2$ is $2$. $\operatorname{gcf}(4, 2) = 2$